Step-by-step tutorial
Step 1
Hot glue is a necessity for this craft, so it is definitely an older child craft or grown-up assisted craft.
Step 2
I filled the walnut shells with hot glue and let it dry just a bit before adding the pick.
Step 3
Once you add the pick it needs to be held for a bit so it stays in the center, but hot glue does dry fast.
Final result!
Once completely dry it was time for a test drive. I closed my eyes as my children added our pirate ships to a large bowl of water.....they float! Thank goodness for that.